The carcass part comprises leg parts that comprise at least a part of the thigh, the carcass part further comprising a saddle that is connected to each of the thighs via the hips, each leg part comprising a free end on the side opposite to the side where it is connected to the saddle. An example of such a carcass part is a back half.
The invention is suitable for anatomic separation of a leg part from a carcass part of slaughtered poultry. This means that the cut or cuts that are made to separate the leg part from the carcass parts do not go through the bones of hip joint. Usually, the hip joints are dislocated in this process to gain better access to tendons and similar tissue that need to be cut through in the separation process.
EPO459580 describes such a device and method. In the device and method of EPO459580, carcass parts such a back halves are brought to the device by an overhead conveyor that is provided with carriers. Each back half is suspended from a carrier; the carrier engages the back halves in the vicinity of the free ends of the leg parts.
When the back half has entered the device of EPO459580, a groin cut is made in the groin area between each leg part and the saddle. Then, a hip dislocating guide pushes the legs apart from each other. Due thereto, the leg parts become disengaged from the carrier of the overhead conveyor. The hip dislocating guide keeps on pushing the legs apart, to such an extent that the hip joints become dislocated and the leg parts come to hang down from the saddle instead of pointing upward, upward being their natural position.
A conveyor is provided in the device of EPO459580 that provides transport of the back halves when they are no longer carried by the carrier of the overhead conveyor. This conveyor engages the saddle.
After dislocation of the hip joints, an incision is made between each leg part and the saddle in the back region of the carcass part using a back cutter in such a way that after making the back incision, a tissue connection remains between the each leg part and the saddle part. The leg parts are therefore still connected to the saddle.
The back half is then conveyed further within the device by a spiked chain that engages the saddle. The back half is supported by a support guide during this movement.
Then, each leg part is gripped by a leg gripper. The leg gripper has a leg gripping slot for engaging a leg part and is moveable along a track that extends horizontally and parallel to the path followed by the saddle. Multiple leg grippers are mounted on an endless chain, of which the top flight runs parallel to the support guide for the saddle.
The leg grippers move at a higher velocity than the velocity at which the saddles are conveyed. So, when a leg gripper engages a leg part, the leg is moved faster than the saddles. This produces a pulling action that separates the leg parts from the saddle.
According to the disclosure of EPO459580, the direction in which the leg parts are pulled off the saddle is essential for harvesting the oyster meat together with the leg parts in a reliable way.
In general, the device and method of EPO459580 functions in a satisfactory way. However, the device is complex and therefore expensive. It also takes up quite some floor space.